Coaxial cable splicer



Feb. 2, 1960 G. E. METCALF, JR 2,923,806

COAXIAL CABLE SPLICER 5 Sheets-Sheet 1 Filed March 28, 1958 INVENTOR. 60) 6'. M572 1/; 4/1?- BY /477'0fA/6'Y q Feb. 2, 1960 G. E. METCALF, JR 2,923,806

COAXIAL CABLE SPLICER Filed March 28, 1958 5 Sheets-Sheet 2 INVENTOR. 61/ 4'. Marni, 4e. BY WM.

Feb. 2, 1960 G. E. METCALF, JR 2,923,806

COAXIAL CABLE SPLICER Filed Mafch 28, 1958 s Sheets-Sheet a U ir d i ws P m COAXIAL CABLE SPLICER Guy E. Metcalf, Jr., Cedar Vale, 'Kans. Application March 28, 1958, Serial No. 724,780 5 Claims. (Cl. 219-57) (Granted under Title 35, US. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the United States Government for governmental purposes without royalty thereon.

This invention relates generally to the splicing of coaxial cables and, more particularly, to a means of splicing and waterproofing the spliced connections between individual lengths of coaxial cable.

In the utilization of coaxial cable for remoting video information, a number of one-thousand foot cable lengths connected together are required. The usual connectors on each end of these cable lengths do not provide a watertight connection, resulting in a poor signal to noise ratio as well as an excessive amount of alternating current hum on the video signals supplied to the remote indicator. Moreover, it was normally found to be practically impossible to dry out collection of moisture in the coaxial cable braid between the outer jacket and the dielectric. The latter resulted in a shorting-out of the wet cable connections effecting an unreliable video signal received at the remote site, as for example, in radar approach controls and ground-controlled approach (GCA )aircraft landings. The coaxial cable splicer of the present invention has been developed in order to eliminate the above-described problem.

It is an object of the present invention, therefore, to provide a unique means of connecting individual lengths of coaxial cable.

It is a further object of the invention to provide a novel cable splicer device for waterproofing the connection between individual lengths of coaxial cable.

A still further-object of the invention is to utilize a device for joining cable lengths together by means of fusion through the application of constant pressure and heat.

Another object of the invention resides in a mechanism for joining cable lengths by the application thereto of external material.

A still further object of the invention is in a system payment to me of any I for joining the ends of cable lengths through constant pressure controlled by a constant weight acting through a piston.

An additional object of the invention resides in a cable splicer device that eliminates shorting out of wet cable connections at inappropriate moments making for an inoperative signal received at a remote site.

Other objects and advantages of the invention will become apparent from the following description taken in connection with the accompanying drawings, in which like reference characters refer to like parts in the several figures.

Fig. 1 is an isometric view of the cable splicer of the present invention, illustrating the splicing and molding sections in assembled condition. V

Fig. 1a .is a bottom perspective view of the heater assembly unit utilized with the inventive cable splicer of Fig. 1, illustrating additional details of the combination heater and upper mold assembly.

Fig. 2 is a top view of the cable splicer of Fig. 1, illustrating additional details of the splicing and molding sections with the cable lengths to be spliced and molded in mounted condition.

Fig. 2a is an enlarged somewhat top perspective view of the molding section of the cable splicer of Fig. 1.

Fig. 3 is a side elevation view, illustrating additional details of the upper and lower splicer right hand or fixed jaws utilized with the inventive cable splicer of Fig. 11.

Fig. 3a is an enlarged side perspective view showing details of the mounting means for the upper and lower splicer right hand or fixed jaws of Fig. 3.

Fig. 4 is a top perspective view of the rod-mounting bracket of the invention, illustrating details of its attachment to the upper and lower splicer left hand or movable aws.

Fig. 5 is a cross-sectional view taken about on line 55 of Fig. 2 of the cable mold bracket assembly illustrating additional details of the cable mold clamps and bracket utilized with the present invention.

Figs. 6, 6a, 6b and 6c, respectively, are schematic, partly broken away, views representing the various conditions of the cable utilized with the cable splicer of the present invention after the molding thereof has been accomplished.

Figs. 7, 7a, 7b and 7.0, respectively, .are schematic, partly broken away, views representing the various stages of the cable to be spliced during the preparation thereof for use with the cable splicer of the present invention.

Fig. 8 is a schematic view of the Wiring diagram that may be utilized with the cable splicer of the instant invention in order to perform the necessary splicing .and molding operations.

Referring specifically to Figs. 7, 7a, 7b and 7c of the drawings, the cable to be spliced is generally indicated at 57 in various stages of necessary preparation before being mounted in the cable splicer of the invention. First, a one and one-half (1 /2) inch section of the outer cable jacket 58 (Fig. 7) is cut and removed with precaution taken to ensure that the exposed cable shield 59 is not cut or damaged in any way. Next, a one-half /2) inch section of cable shield 59 (Fig. 7a) is fanned out .perpendicular to the cable but without unbraiding to expose the polyethylene dielectric 60. The fanned section 59a of cable shield 59 (Fig. 7b) is then pushed back as close as possible to the cut portion of the outer jacket with said fanned section being maintained perpendicular to the cable. Next, a one-half /z) section of the exposed dielectric 60 and center conductor 61 is sharply cut off. This latteroperation is preferably accomplished by using a sharp knife and working the knifearound the circumfer ence of dielectric 60 until it is completely cut through and inner conductor 61 is heavily nicked. At this time, the exposed end of dielectric 69 is bent back and forth and around until the center conductor 61 breaks off where it is heavily nicked. Precaution should be ,made to ensure that the end of the inner conductor 61 is cut square in order to provide a proper welding surface. .A one-fourth A1) inch section of center conductor 61 is then exposed by cutting through the polyethylene dielectric 60 at an angle of approximately 45 (note Fig. 7b) beginning at a distance of five-sixteenths (5/ of an inch back from the end of the cable and ending at the center conductor 61 approximately one-fourth 4.) inch from the end of the cable 57. In all, four cuts are made around the circumference of the dielectric 60, each cut being approximately from the previous one. After this latter cutting operation is completed, the dielectric 60 is rolled in a circular motion between the fingers until it becomes loose enough to pull off center conductor 61 with precaution being taken to ensure'that said center conductor 61 is not bent in'any-manner. Withthe abovedescribed cutting operation, dielectric 60 has been cut in such a manner to present the maximum surface to-be welded as well as for the new material to adhere. Moreover there is less tendency to nick or damage and therefore weaken center conductor 61. After the abovedescribed preparation of the cable to be spliced is performed on the second cable (Fig. 70), both cables are now ready for the splicing of their center conductors 61 in a'manner to be hereinafter described in detail.

' With particular reference to Figs. 1 and 2 of the drawings; the cable splicer assembly of the present invention preferably includes an aluminum case 1 having a Bakelite or other hard plastic top cover plate 2 and an aluminum bottom cover plate 3. Positioned on the top cover plate 1 is the rod-mounting bracket 4 which mounting bracket 4 is afiixed thereto by means of the screws 25. *Affi'xed to said top cover plate 1 adjacent to but spaced from one end of said mounting bracket 4 as by means of the screws 36 is the fixedly mounted right hand splicer clamp bracket 10. Riveted .to the side of said bracket 10 adjacent one end of said mounting bracket 4 as by means of the rivets 34 are the lower and upper right-hand fixed steel jaws 8 and 9, respectively, of the right-hand or fixed splicer clamp indicated generally at 55. Movably positioned adjacent to and between said fixed splicer clamp '55 and said mounting bracket 4 is the movable left hand steel splicer clamp 56 consisting of the lower and upper left-hand movable steel jaws 6 and 7, respectively, which jaws 6 and 7 are mounted for appropriate movement in a manner to be hereinafter described in detail. Positioned within said mounting bracket 4 are a pair of slidably positioned round brass conducting rods 27a and 27b extending through the end of said bracket 4 remote from said splicer clamps 55, 56 for a purpose to be hereinafter explained in detail. One end of each brass rod 27a, 27b is afiixed to said movably mounted left-hand splicer clamp 56 in a manner to be described in detail hereinafter. A microswitch 12 having a cover plate 11 afiixed thereto as by means of screws 31 is mounted on top cover plate 2 and incorporates a switch contact 12a in engagement with the end of said slidably mounted rod 27a extending through one end of bracket 4 for a purpose to be hereinafter described in detail. It is noted that the micro- 1 switch 12 is in circuit with a power transformer 38 (note Fig. 8) which transformer is mounted beneath top cover plate 2 by means of suitable screws 25 and is electrically connected to a suitable main source of 115 volt, 50/60 cycle power by means of the rubber service cord 22. Moreover, brass rods 27a, 27b are respectively in circuit with the same transformer by means of said microswitch 12 and the secondary lead wire shown broken away at 53 mounted in copper tubing 37 in Fig. 4 of the drawings, for example. In addition, microswitch 12 is operated to its cocked or welding position (that is, switch 12 is closed) in a manner to be described hereinafter when the weld material is in position; however, as the weld material melts and fuses together, the inherent spring action of .said microswitch pushes weld materials together resulting in opening of the main switch 12 and thus automatically stopping the welding operation; I

Referring again to Fig. 1 and also to Figs. 2 and 2a of the drawing, the coaxial cable mold bracket is indicated at as mounted on top cover plate 2 on the opposite side thereof from the mounting bracket 4 previously mentioned as by means of the screws 25. Said mold bracket 5 may consist of a one-eighth (Ms) inch flat steel plate having one edge thereof formed with a pair of spaced upright supports 5a adjacent each end thereof for supporting a lower steel or brass cable mold end clamp 44 thereon which lower mold end clamp 44 is silver soldered to said upright supports 5a. In addition, a lower copper cable center mold 20 is silver soldered on an additional pair of spaced upright supports 5b formed on the edge of said mold bracket 5 half way between upright end supports 5a. Each ofsaid lower mold end clamps 44 is provided with a cable mold clamp yoke assembly 16. As seen clearly in Figs. 1 and 5 of the drawings, said clamp yoke assembly 16 consists of an upper cable mold end clamp 43 complementally disposed relative to said lower cable mold clamps 44, a cable mold end clamp yoke 42 silver soldered to said upper cable mold end clamp 43, and a screw 13'. and wing nut 19 for retaining or locking said clamp yoke 42 and. upper cable mold end clamp 43 soldered-thereto in position and clamping the respective ends of the cable lengths 57 to be spliced. As seen clearly in Figs. 2a and 5 of the drawings, coaxial cable mold bracket 5 incorporates a projecting slotted surface indicated generally at 50 and extending between each respective pair of upright supports 5a and 5b. Each cable mold end clamp yoke 42 tapers downwardly into a portion 42a (note Fig. 5) terminating in a narrowed bottom portion 42b extending at right angles thereto into the open space between respective upright supports 5a. Each screw 18 is afiixed at one end as by silver soldering to said narrowed bottom portion 42b and extends through a respective slot of the slotted surface 50 at its other end where it is engaged with wing nut 19 for appropriate adjustment and clamping. A similar projecting slotted surface 5d extends between the upright supports 5b of the lower cable center mold 20 with an identical sists of a heater assembly 15a incorporating a heater cartridge 33, and an upper mold assembly 15b consisting of a cylinder 15c, piston rod 14 for insertion at its lower end into said cylinder 15c, and a weight 13 which may consist of a tin can filled with lead mounted on the upper end of piston rod 14 fora purpose to be hereinafter explained in detail. In addition, an electrical cord 51 is attached at one end to the heater cartridge 33 of heater assembly 15a and extends through an opening (note Fig. 1) in top cover plate 1 for connection in circuit with transformer 38, as shown in Fig. 8 of the drawings. Moreover, a push button switch 28 and a toggle switch 29 are mounted on top cover plate 2 (Fig. l) and are utilized, respectively, to energize the welding circuit and the heater assembly unit (note Fig. 8).

With specific reference to Figs. 3 and 3a of the drawings, it is clearly seen that the right-hand fixed splicer clamp 55 consisting of lower jaw 8 and upper jaw. 9 under clamping pressure-of helical spring 26 incorporates a clamp wire guide indicated generally at 54 and consisting of an identical pair of brass welding rods 54a, fie of an inch in diameter and length, silver soldered in openings adjacent the ends of said jaws 8 and 9 and contacting each other. An identical clamp wire guide as 54 is incorporated on the lefthand movable splicer clamp 56 consisting of lower and upper jaws 6 and 7. A 0.024 inch hole indicated at 54b in Fig. 3 is drilled through said pair of welding rods 54a in both sets of assembled clamps and it is these two holes in the respective fixed and movable clamps 55, 56 that are utilized for holding or clamping the sections of wire cable to be welded and spliced under a pressure of approximately 5 pounds as accomplished by helical steel spring 26 rigidly mounted between respective rear ends of jaws 6, 7, 8 and 9 as by rivets 35; however, before the welding rods 54a are actually silver soldered in the afore-mentioned openings in said left and right hand clamps 55, 56, each of said openings is machined so that the centers of the inch diameter brass welding rods 54a are fiush with the respective bottom edges :05 each jaw 6, 7, 8 and 9; Then,'lower fixed and movable jaws 6 and 3 are assembled to their respective mounting means, fixed splicer clamp bracket and movable splicer clamp-mounting bracket 40 (note Fig. 4) with a 0.01 inch clearance therebetween, and opposite welding rods 54a mounted in each jaw 6 and 8 are adjusted to make contact equidistant between brackets 10 and 40. At this time, welding rods 54a are silver soldered in position. One important feature resides in the grinding off of approximately 0.005 inch material between the upper and lower welding rods 54a to ensure a flat contact surface on each half thereof and to make upper and lower jaws 6, 7, 8 and 9, respectively, parallel and separated by of an inch. In addition, each of weld ing rods 54a are mounted at an angle of 7 /2 05 center in the openings provided in each jaw 6, 7, 8 and 9 in order to insure that the wire cable sections to be spliced are mounted in a straight line relative to each other, since the splicer clamps 55, 56 are mounted at an angle of to each other. As clearly illustrated in Fig. 3a of the drawings, the previously mentioned splicer clamp bracket 10 consists of a base section 10a securely bolted to the top cover plate 2 and an upright bifurcated section 10b into which the lower jaw 8 is rigidly assembled as by a pair of rivets 34 and the upper jaw 9 is pivotally assembled by a single rivet 34. It is between the sides of said bifurcated section 10b that the previously mentioned 0.010 inch clearance is provided. It is noted that said base section 10a is electrically connected in circuit with power transformer 38 by the secondary lead wire 52 as seen in Fig. 2 of the drawings.

With particular reference to Fig. 4 of the drawings, the movable splicer clamp mounting bracket 40, which is utilized to mount and assemble the movable left-hand clamp consisting of lower and upper jaws 6 and 7, respectively, is made primarily in two main parallel sections or side walls 40a and 40b connected together at the middle by a center strip 40c. Lower jaw 6 is assembled between walls 40a, 40b in contact with the lower surface of center strip 400 whereas upper jaw 7 is assembled between Walls 40a, 40b in contact with the upper surface of center strip 400. Again, lower jaw 6 is affixed to bracket 40 by a pair of rivets 34 and upper jaw 7 pivoted thereto by single rivet 34. As clearly illustrated, side wall 40a adjacent to mounting bracket 4 is silver soldered to a respective end of each of the rods 27a, 27b which rods are slidably mounted in said mounting bracket 4. As viewed in said Fig. 4, rod 27b is attached at its other end and to the previously mentioned secondary lead wire 53 which lead wire 53 is in circuit with the transformer 38 (note Fig. 2). Rod 27a is engaged at its end remote from bracket 40 with the switch contact arm 12a of microswitch 12 (note Fig. 1) for a purpose to be explained hereinafter in detail.

The splicing operation of the present invention will now be described in detail with particular reference to Figs. 1, 2 and 4 of the drawings. After the two cable ends to be spliced have been prepared in the manner previously explained, the prepared end of one center conductor 61 of one of said cables is inserted within the hole 54b (note Fig. 3) formed between welding rods 54a of the fixed splicer clamp 55 and is extended therethrough towards the movable splicer clamp 56 approximately ,4 of an inch. The end of the other center conductor 61 is then inserted in an identical hole 54b of splicer clamp 56 and it is also extended therethrough towards splicer clamp 55 approximately 4 of an inch. Initially, the pressure of fixed splicer clamp 55 is slightly released, and the wire therein is forced against the wire in the movable clamp 56 until the latter has moved slightly to the left (as viewed in Fig. 4) past the point where an audible click is heard in microswitch 12. This latter operation is, .of course, accomplished due to the engagement between the end of brass welding rod 27a and switch contact arm 12a. At this point, the clamping pressure of fixed clamp 55 is reapplied since said click indicates that microswitch 12 is cocked and the wires to be spliced are in correct position for welding. The weld button or push button switch- 28 is then actuated resulting in a momentary dull red glow at the point of weld between the two center conductors 61. If, however, a sparking action should occur, this indicates a bad weld and recocking of microswitch 12 and repetition of the latter step is then necessary. After welding is completed, the wires are removed from the fixed and movable clamps 55, 56 and the welded area is scraped lightly with a knife. At this time, the wire braid 59a that had been previously fanned out is checked to ensure that it is still perpendicular tothe cable 57. Next, the spliced cable 57 is placed in the molding section of the inventive splicer with the exposed center conductor 61 in the center cable mold 20 and adjacent end portions 58 in oppositely disposed lower cable mold end clamps 44. One upper cable mold end clamp 43 and the cable mold clamp yoke 42 soldered thereto is complementally engaged over the top of one end portion 53 of the spliced cable and tightened securely in place. The oppositely disposed upper cable mold end clamp 43 and cable mold clamp yoke 42 is loosely complementally engaged over the top of the other end portion 58 of the spliced cable and this end of said cable pulled with a pressure of approximately 25 lbs. to ensure proper centering of the exposed center conductor 61 in lower center cable mold 20 at which point, upper cable mold end clamp 43 and cable mold clamp yoke 42 on the latter end are securely tightened in place. It is noted that it is most important that correct centering of the exposed wire or center conductor 61 be ensured, since any deviation of the conductor from the correct center position changes the characteristic impedance at that point and results in reflections of the primary signals on the line and degeneration of the display on the remote indicator. After the spliced wire or center conductor 61 has been correctly fastened in the molding section as described above, the upper cable center mold 20a of the combination heater and upper mold assembly unit 15 is placed over said exposed wire or center conductor 61 in the lower center cable mold 20 and securely fastened in place by means of the center mold clamp yoke '17. The upper mold assembly indicated at 151) in Fig. 1 consists of a cylinder 15c containing a supply of prepared polyethylene that extends to approximately /2 inch below the top of said cylinder 15c. Piston rod 14 is inserted into cylinder 15c and applies continuous pressure on the prepared polyethylene therein by means of the weight 13. Therefore, whenheater toggle switch 29 is actuated to energize heater assembly 15a and thereby heat the cylinder 150, the prepared polyethylene therein is forced out through the extrusion hole 15d (note Fig. la) into the lower cable center mold 20 to cover center conductor 61. The weighted upper mold assembly 15b is not removed until a slight amount of polyethylene has extruded out both ends of said cable center mold 20 and allowed to cool. It is noted that it is necessary to cut off heater switch 29 after a few seconds only if the molding operation is started at room temperature. If cooler temperatures prevail, however, switch 29 is left on for a longer period. After the extruded polyethylene material has cooled, the weighted piston rod 14 is removed from cylinder by twisting weight 13 in a circular motion and pulling upwardly. The combined heater and upper mold assembly unit 15 and cable mold end clamps 43 and yokes 42 are removed. The cable 57 is then removed from the mold section and the spliced section, center conductor 61, examined for air bubbles, poor seal or misalignment of the center conductor and, if so, the entire spliced.

area is cut out and the above described procedure is. repeated.

Referring particularly to Figs-6, 6a, 6b and 6c of the drawings, the spliced cable is shown generally at 57 and consists of two cable sections each having an outer cable jacket 58, an exposed cable shield 59 with a'fanned section 59a, a polyethylene dielectric 60 and a center conductor 61, the latter having been molded together as a single unit intliemanner previously described. In addition, excess polyethylene indicated at 61c has been formed on the surface of dielectric 60 during the molding process described above. This excess is neatly trimmed off by a sharp knife. Next, one of the loose cable shields 59 is slid back in its proper position over exposed dielectric 60. Said cable shield 59, which should be as snug as possible against dielectric 60 with fanned out section 59a still braided, is held in place by wrapping with approximately twenty turns of #30 wire indicated at 62 in Fig. 6a of the drawings. The other loose cable shield 59 is likewise slid back into its proper position over the remaining portion of exposed dielectric 61 in overlapping and tight relation to said first cable shield and then securely fastened with approximately twenty turns of #30 wire as seen at 62 in Fig. 612. A slight amount-of soldering paste is applied to the overlapped portion of said shields. Finally, after preheating a substantial amount of solder is applied to the overlapped portions of cable shield 59 with said overlapped portions being twirled very rapidly. Precaution should be taken not to attempt a perfect solder connection on the entire overlapped portions since excessive heat will melt the polyethylene and thus destroy the impedance characteristics of cable 57. The spliced area of cable 57 is then wrapped with a overlap layer of vinyl tape with the tape overlapping outer cable jacket 58 one inch on each end as illustrated at 63 in Fig. 6c of the drawings. This taped area is then dipped in liquid vinyl, allowed to dry forat least one hour, and then redipped. It is noted that should the liquid vinyl thicken because of exposure to air, it may be thinned with any appropriate paint thinner.

I claim:

1. A cable splicer machine for splicing cable sections together comprising an outer case having a top cover insulated plate, a bottom cover plate and a power transformer positioned within said outer case in depending mounted condition on the inside of said top cover plate, a rodmounting bracket aflixed on said top cover plate having a pair of spaced parallel and elongated rods at least one of which being a conducting rod in circuit with said transformer, a fixed splicer clamp bracket fixed on said top cover plate spaced from one end of said rod-mounting bracket, a fixed rotatably mounted splicer clamp positioned on said fixed splicer clamp bracket adapted to receive one cable section to be spliced, a. movable splicer clamp bracket between said fixed splicer clamp bracket and one end of said rod-mounting bracket attached to said pair of rods, a movable rotatably mounted splicer clamp positioned within said movable splicer clamp bracket adapted to receive the other cable section to be spliced, and a microswitch in circuit with said transformer and engaged with one of said pair of rods at the end thereof remote from its attachment to said movable splicer clamp bracket, said microswitch movable between an uncocked position and a cocked welding position to weld the two ends of said cable section.

2. A cable splicer as in claim 1, said fixed splicer clamp comprising a lower fixed jaw affixed to said fixed splicer clamp bracket and an upper jaw rotatably positioned on said fixed splicer clamp bracket with a helical spring positioned between adjacent ends of said lower and upper jaws applying a clamping pressure of a predetermined amount on opposite ends thereof, each' of said jaws incorporating a complementally disposed semicircular opening on the ends thereof remote from said spring, and a clamp wire guide consisting of a pair of welding rods soldered within said openings in contact with each other and having a hole drilled therethrough in the area of contact between said welding rods receiving the end of one cable section to be spliced, said movable splicer clamp comprising an identical lower and upper jaw affixed to said movable splicer clamp bracket and having an identical pair of welding rods forming a second clamp wire guide receiving the end .of a sec- 0nd cable section to be spliced, said last-named splicer clamp bracket being moved towards said rod-mounting bracket to move one'of said pair'of rods atfixed to said movable splicer clamp bracket to 'cock the microswitch en'- gaged therewith to its welding position, and a weld push button for energizing said power transformer and said welding'rods in circuit therewith. a

3. In a cable splicingmachine for splicing cable, means for Welding the exposedends of two cable sections comprising a main supporting structure having a top cover plate, a power transformer positioned within said main supporting structure beneath said top cover plate, a fixed splicer clamp mounted on said top cover plate supporting the first of said cable sections with the exposed end thereof facing inwardly and electrically connected with said transformer, a movable splicer clamp mounted adjacent said fixed splicer clamp supporting the second of said cable sections with the exposed end thereof facing inwardly towards and in contact with the exposed end of said first cable section equidistant between said splicer clamp, a first brass rod supported on said top cover plate having one end aflixed to said movable splicer clamp, a second brass rod supported on said top cover plate spaced from and parallel to said first brass rod afiixed to said movable splicer clamp and electrically interconected with said power transformer, a microswitch in circuit with said power transformer in contact with said first brass rod and movable to its cocked welding position by said first brass rod on movement of said movable splicer clamp to a predetermined position, and a push button switch for energizing said power transformer and closing a circuit through at least one of said pair of rods to weld the exposed contacting ends of said cable sections.

4. In a cable splicer machine, means for welding the exposed ends of two cables to be spliced, said means comprising a pair of splicer clamps mounted adjacent to each other and each incorporating a wire guide containing the cables to be spliced with the exposed end of each cable extending inwardly to a contacting position at the midpoint between said clamps, a source of welding material incorporated within each of said pair of splicer clamps in surrounding relation to each of said cables, a main power supply including a power transformer in circuit with said splicer clamps, a microswitch in circuit with said power transformer, and conducting means between said microswitch and one of said splicer clamps, said lastnamed splicer clamp being movably mounted to initially close said microswitch through said conducting means when said welding material is in position and to auto rnatically effect subsequent opening of said microswitch under spring pressure when said welding material melts and flows together.

5. in a cable splicer machine as in claim 4, said conducting means comprising a rod-mounting bracket positioned adjacent said movably mounted splicer clamp, and

a pair of rods mounted in spaced, parallel relation in said bracket and extending through opposite ends of said bracket, one of said rods aifixed at one end to said movable splicer clamp and engaging said microswitch at its other end to move said microswitch to its welding position, the other of said rods being composed of conductive material and affixed at one end to said movable splicer clamp and at its other end to the secondary lead line of said power transformer.

References Cited in the fileof this patent UNITED STATES PATENTS Arrain Sept. 24, 1957 

